Sexual size dimorphism and male contest in wild Siamese fighting fish

Abstract

Larger males of the wild Siamese fighting fish Betta splendens were more successful in male contests. There were no differences in fighting duration among treatments. Comparing agonistic behaviour between large and small males in 1 and 2 .. treatments, larger males attacked, chased and performed total agonistic behaviour more than smaller males. There were no differences between larger and smaller males concerning other agonistic behaviour during fighting. Females presented with two potential mates of different sizes did not prefer larger males. 2001 The Fisheries Society of the British Isles

<htm>Estrutura populacional de <i>Mimagoniates microlepis </i>(Steindachner, 1876) (Characidae, Glandulocaudinae) em um riacho de Floresta Atlântica, Paraná (Brasil)</htm>

“…Por outro lado, quando os machos são maiores, outros fatores estarão atuando com maior intensidade na seleção sexual. Em diversas espécies de peixes, machos maiores tendem a vencer confrontos entre machos, mantêm territórios de melhor qualidade e obtêm maior acesso às fêmeas (JAROENSUTASINEE & JAROENSUTASINEE, 2001;PYRON, 1996;CHELAPPA et al, 1999). Mimagoniates microlepis é uma espécie que apresenta comportamento agonístico e de corte elaborados (NELSON, 1964;WEITZMAN et al, 1988).…”

Four-Week Fluoxetine (SSRI) Exposure Diminishes Aggressive Behaviour of Male Siamese Fighting Fish (&lt;i&gt;Betta splendens&lt;/i&gt;)

“…They are also cultivated as ornamentals and are readily available in pet stores around the world. Males of this species exhibit strong and stereotyped aggression in defending their territories against intruding male conspecifics [3]. Patterns of aggression behavior include frontal displays (erecting the operculate, fins, and tail while facing opponent accompanied by erection of fins and tail), and physically attacking and biting the intruder.…”

A Non-social and Isolate Rearing Condition Induces an Irreversible Shift toward Continued Fights in the Male Fighting Fish (Betta splendens)

“…The males are known to have a characteristic repertoire of agonistic behaviors such as gill-cover erection (Simpson, 1968). The male fights are serious, and often involve physical damages to the opponent fish; on the other hand, females are smaller and duller in color, and do not fight so aggressively (Jaroensutasinee and Jaroensutasinee, 2001), suggesting a functional link between the aggression and the reproduction. Actually, males make and defend a bubble nest on the water surface, and solely provide parental care for developing eggs and fry.…”